Extreme ultraviolet light generation method, extreme ultraviolet light source assembly and optical system

Abstract

The embodiment of the invention provides an extreme ultraviolet light generation method, an extreme ultraviolet light source assembly and an optical system. The extreme ultraviolet light generation method comprises the following steps: generating plasma by using a magnetic confinement device; under the condition that the plasma meets the preset injection condition, the heavy metal injection device is controlled to inject specified heavy metal into the magnetic confinement device, so that the specified heavy metal acts with the plasma in the magnetic confinement device to generate extreme ultraviolet light; the optical device is controlled to collect the extreme ultraviolet light. The magnetic confinement device meeting the extreme ultraviolet light generation requirement is low in cost, simple and stable in operation and high in electro-optical conversion efficiency, so that the extreme ultraviolet light generation method improves the stability of the extreme ultraviolet light and reduces the extreme ultraviolet light generation cost.

Description

Technical Field

[0001] Embodiments of the present application relate to the field of semiconductor technology, and in particular, to a method for generating extreme ultraviolet light. Background Art

[0002] As chip integration continues to increase, the feature size of photolithography is required to be continuously reduced. Extreme ultraviolet (EUV) light source is a newly developed light source. The wavelength of exposure light generated by the EUV light source is 13.5 nanometers or less. When the EUV light source is applied to the exposure system, very small photolithography feature sizes can be obtained.

[0003] At present, the mainstream method of generating extreme ultraviolet light is laser produced plasma radiation (LPP), the principle of which is: a laser source generates a laser beam to bombard a tin (Sn) target, thereby exciting plasma, and the plasma radiates extreme ultraviolet light outward. However, the laser produced plasma radiation method still has many problems such as high cost, short life, and poor stability. Therefore, a low-cost and stable extreme ultraviolet light generation solution is urgently needed. Summary of the invention

[0004] In view of this, an embodiment of the present application provides a method for generating extreme ultraviolet light. One or more embodiments of the present application also relate to an extreme ultraviolet light source assembly and an optical system to solve the technical defects existing in the prior art.

[0005] According to a first aspect of an embodiment of the present application, a method for generating extreme ultraviolet light is provided, comprising:

[0006] Generate plasma using magnetic confinement device;

[0007] When the plasma meets the preset injection conditions, the heavy metal injection device is controlled to inject the specified heavy metal into the magnetic confinement device, so that the specified heavy metal reacts with the plasma in the magnetic confinement device to generate extreme ultraviolet light;

[0008] Control optics to collect extreme ultraviolet light.

[0009] According to a second aspect of an embodiment of the present application, there is provided an extreme ultraviolet light source assembly, comprising a magnetic confinement device, a heavy metal injection device and an optical device, wherein the heavy metal injection device is connected to the magnetic confinement device;

[0010] a magnetic confinement device for generating plasma;

[0011] A heavy metal injection device, used to inject a specified heavy metal into the magnetic confinement device when the plasma meets a preset injection condition, so that the specified heavy metal reacts with the plasma in the magnetic confinement device to generate extreme ultraviolet light;

[0012] Optical device for collecting extreme ultraviolet light.

[0013] According to a third aspect of an embodiment of the present application, an optical system is provided, comprising the extreme ultraviolet light source assembly provided in the second aspect above.

[0014] An embodiment of the present application provides a method for generating extreme ultraviolet light, which uses a magnetic confinement device to generate plasma; when the plasma meets the preset injection conditions, the heavy metal injection device is controlled to inject a specified heavy metal into the magnetic confinement device, so that the specified heavy metal reacts with the plasma in the magnetic confinement device to generate extreme ultraviolet light; and the optical device is controlled to collect the extreme ultraviolet light. Since the magnetic confinement device that meets the requirements for generating extreme ultraviolet light has a low cost, simple and stable operation, and a high electro-optical conversion efficiency, the stability of the extreme ultraviolet light is improved, and the cost of generating extreme ultraviolet light can also be reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 is a flow chart of a method for generating extreme ultraviolet light provided in one embodiment of the present application;

[0016] Figure 2 This is a structural diagram of an extreme ultraviolet light source assembly provided by one embodiment of the present application;

[0017] Figure 3 This is an architectural diagram of an optical system provided by an embodiment of the present application.

[0018] Reference numerals

[0019] 100—magnetic confinement device, 200—heavy metal injection device, 300—optical device, 400—monitoring device, 500—control device, 600—data acquisition device;

[0020] 1002—vacuum chamber, 1004—magnet, 1006—magnet power supply, 1008—RF power source, 1010—RF wave antenna, 1012—air pump group, 1014—intake valve assembly. DETAILED DESCRIPTION

[0021] Many specific details are described in the following description to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways than those described herein, and those skilled in the art can make similar generalizations without violating the connotation of the present application, so the present application is not limited by the specific implementation disclosed below.

[0022] The terms used in one or more embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to limit one or more embodiments of the present application. The singular forms of "a", "said" and "the" used in one or more embodiments of the present application and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings. It should also be understood that the term "and / or" used in one or more embodiments of the present application refers to and includes any or all possible combinations of one or more associated listed items.

[0023] It should be understood that, although the terms first, second, etc. may be used to describe various information in one or more embodiments of the present application, these information should not be limited to these terms. These terms are only used to distinguish the same type of information from each other. For example, without departing from the scope of one or more embodiments of the present application, the first may also be referred to as the second, and similarly, the second may also be referred to as the first. Depending on the context, the word "if" as used herein may be interpreted as "at the time of" or "when" or "in response to determining".

[0024] First, the terms involved in one or more embodiments of the present application are explained.

[0025] Photolithography: Photolithography is an important step in the semiconductor device manufacturing process. This step is to form a photolithography pattern in the photoresist layer using an exposure process and a development process. However, with the continuous improvement of chip integration, this requires the feature size of photolithography to be continuously reduced. According to the diffraction limitation theory of light, the minimum feature size that can be resolved by a light wave is proportional to its wavelength, so shorter wavelength light is more conducive to obtaining higher precision photolithography imaging.

[0026] Tokamak: When electricity is applied, a huge spiral magnetic field is generated inside the Tokamak, heating the plasma inside to a very high temperature to achieve the purpose of nuclear fusion.

[0027] Magnetic Mirror: It is a magnetic field configuration formed by arranging two coils with the same current direction with their central axes overlapping. The magnetic field is strongest at the center of each coil and weakest in the middle of the coil.

[0028] Stellarator: Stellarator refers to a magnetic confinement fusion experimental device with an external spiral winding. It consists of a closed tube and an external coil. The closed tube is in a straight line, a "racetrack" shape, or a space curve. Common stellarators have two or three pairs of spiral windings. The former has a magnetic surface shape similar to an ellipse, while the latter is approximately a triangle. When equal and opposite currents are passed through adjacent spiral windings, the magnetic field generated by the spiral windings is combined with the longitudinal magnetic field, and the magnetic lines of force undergo a rotational transformation, thereby confining plasma without longitudinal current.

[0029] Field Reversed Configuration: Field Reversed Configuration (FRC) is a linear device. When the reverse current of the plasma inside the field reversed configuration is larger than the magnetic mirror magnetic field generated by the current of the external coil, the internal magnetic field will reverse in some areas, forming a closed magnetic field structure.

[0030] Reverse field pinch: It is a type of annular magnetic confinement fusion device. Its main feature is that the magnetic field that confines the plasma is generated by the internal current of the plasma. It has the advantages of pure ohmic heating to achieve fusion ignition conditions and high quality power density.

[0031] Plasma: Plasma is a form of matter that is mainly composed of free electrons and charged ions. Under common circumstances, plasma is usually formed under high temperature, high energy or strong electric field conditions. One common way is to heat the gas so that the atoms or molecules in the gas gain enough energy to ionize and form plasma.

[0032] With the development of semiconductor manufacturing technology and nuclear fusion technology, how to generate extreme ultraviolet light has gradually become a research focus because very small lithography feature sizes can be obtained when extreme ultraviolet light is applied to exposure systems.

[0033] At present, extreme ultraviolet light is usually generated based on laser-generated plasma radiation. However, laser-generated plasma radiation technology still has many problems such as high cost, short life, and poor stability. The cost of an extreme ultraviolet light source using laser-generated plasma radiation technology is often very expensive. After the tin target used in laser-generated plasma radiation technology is irradiated by the high energy of the laser beam, a very hot plasma will be formed, generating high-energy ions and atoms. These ions and atoms will have a strong impact and corrosion on the tin target, resulting in serious loss and burning of the tin target. In addition, due to the corrosion and burning of the tin target, a large amount of debris and smoke will be generated. These debris and smoke will adhere to the surface of the optical component, affecting the radiation efficiency and stability of the extreme ultraviolet light source.

[0034] In order to solve the above problems, an embodiment of the present application proposes a method for generating extreme ultraviolet light, which uses a magnetic confinement device to generate plasma; when the plasma meets preset injection conditions, the heavy metal injection device is controlled to inject specified heavy metals into the magnetic confinement device, so that the specified heavy metal reacts with the plasma in the magnetic confinement device to generate extreme ultraviolet light; and the optical device is controlled to collect the extreme ultraviolet light.

[0035] It is worth noting that the magnetic confinement device proposed in the embodiment of the present application has the advantages of low cost, simple and stable operation, and high electro-optical conversion efficiency. Specifically, taking the magnetic confinement device as a tokamak as an example, in the process of generating extreme ultraviolet light in the present application, the plasma in the tokamak does not need to reach the nuclear fusion reaction temperature. Therefore, the cost and requirements of the tokamak used to generate extreme ultraviolet light are greatly reduced, and the difficulty of generating extreme ultraviolet light is also greatly reduced. In addition, since the plasma generated by the extreme ultraviolet light source assembly can be well confined in the vacuum chamber of the tokamak by the magnetic field, the corrosion and burning of the emitting light source wall material by the plasma are effectively reduced, thereby extending the life of the extreme ultraviolet light source assembly.

[0036] In the present application, a method for generating extreme ultraviolet light is provided. The present application also relates to an extreme ultraviolet light source assembly and an optical system, which are described in detail one by one in the following embodiments.

[0037] See also Figure 1 , Figure 1 A flowchart of an extreme ultraviolet light generation method provided by an embodiment of the present application is shown, which specifically includes the following steps:

[0038] Step 102: Generate plasma using a magnetic confinement device.

[0039] Specifically, magnetic confinement refers to the use of a magnetic field to constrain the movement of charged particles in a plasma. Magnetic confinement devices include, but are not limited to, any one of a tokamak, a stellarator, a magnetic mirror, a field inversion, and an inverted field pinch. Among them, the tokamak can be a toroidal tokamak or a spherical tokamak. The tokamak includes a vacuum chamber, a magnet, a magnet power source, a radio frequency power source, a radio frequency wave antenna, an air pump group, and an air intake valve assembly.

[0040] It should be noted that before using the magnetic confinement device to generate plasma, the extreme ultraviolet light source assembly can be maintained and repaired to ensure that the extreme ultraviolet light source assembly is in good condition and can operate normally.

[0041] In practical applications, taking the magnetic confinement device as a tokamak as an example, the use of a tokamak to generate plasma may include the following steps: First, the vacuum pump group may be controlled to exhaust the gas in the vacuum chamber to ensure that the vacuum chamber reaches the required high vacuum environment, generally 10 -5 Secondly, the magnet power supply can be started to start the superconducting coil to generate a 1T to 2T toroidal magnetic field at the magnetic axis of the tokamak. Then, the millisecond pulse inlet valve assembly can be started to inject an appropriate amount of high-purity hydrogen into the vacuum chamber. The filling pressure is generally 10 -2 Pa to 10 -3Pa. Finally, the RF power source can be started to couple high-power microwaves or millimeter waves into the plasma through the RF wave antenna. Since the hydrogen has been pre-ionized by hot electrons, the injected 2.45GHz high-power microwaves or millimeter waves can effectively excite and maintain a circular plasma current until the plasma meets the preset injection conditions. The plasma current is generally 100kA.

[0042] Step 104: When the plasma meets the preset injection conditions, the heavy metal injection device is controlled to inject the specified heavy metal into the magnetic confinement device, so that the specified heavy metal reacts with the plasma in the magnetic confinement device to generate extreme ultraviolet light.

[0043] In one or more embodiments of the present application, after generating plasma using a magnetic confinement device, further, when the plasma meets preset injection conditions, a heavy metal injection device can be controlled to inject specified heavy metals into the magnetic confinement device, so that the specified heavy metals react with the plasma in the magnetic confinement device to generate extreme ultraviolet light.

[0044] Specifically, the preset injection condition can be that the plasma reaches a certain temperature and density, such as a density of 10 18 m -3 , electron temperature 10 million degrees, plasma current 100kA. In one embodiment, the plasma is steady-state plasma when it meets the preset injection conditions, and steady-state plasma refers to plasma in steady-state operation. Heavy metals refer to those with a density greater than 4.5g / cm 3 The designated heavy metal refers to a metal element that can produce strong extreme ultraviolet light, and the designated heavy metal includes at least one of tin powder, tungsten powder, nickel powder, and tantalum powder.

[0045] Furthermore, after the plasma is generated by the magnetic confinement device, the heavy metal injection device can be controlled to inject the specified heavy metal into the magnetic confinement device, and the injection rate and angle of the specified heavy metal can be appropriately adjusted to ensure that the target mass of the specified heavy metal is excited to generate extreme ultraviolet light. For example, if the specified heavy metal is tin powder, and the electron density is 10 18 m -3 , the atomic density of tin is 10 15 m -3 , the electron temperature is 10 million degrees. According to the following formula (1), it can be estimated that the impurity radiation power of tin is in the order of 100W, which is enough to produce extreme ultraviolet light and can be further increased by increasing the density.

[0046] P R =n e n I R (1)

[0047] Among them, P R represents the radiated power, ne represents the electron density, n I represents the tin atomic density and R represents the electron temperature.

[0048] In practical applications, when the heavy metal injection device injects the specified heavy metal into the magnetic confinement device, one of tin powder, tungsten powder, nickel powder, and tantalum powder can be selected. There are many ways for the heavy metal injection device to inject the specified heavy metal into the magnetic confinement device, which are selected according to actual conditions, and the embodiments of the present application do not impose any limitation on this.

[0049] In a possible implementation of the present application, the heavy metal injection device can intermittently inject specified heavy metals into the magnetic confinement device.

[0050] In another possible implementation of the present application, in order to ensure the stability of the extreme ultraviolet light source, the heavy metal injection device can continuously inject the specified heavy metal into the magnetic confinement device, that is, the above-mentioned control of the heavy metal injection device to inject the specified heavy metal into the magnetic confinement device may include the following steps:

[0051] The heavy metal injection device is controlled to continuously inject a target mass of a designated heavy metal into the magnetic confinement device.

[0052] Specifically, the target mass refers to the mass value of the designated heavy metal injected into the magnetic confinement device, and the mass value includes but is not limited to the weight value and the volume value.

[0053] In practical applications, the heavy metal injection device can inject specified heavy metals into the magnetic confinement device at a specified rate and specified angle. The specified heavy metals are heated in the magnetic confinement device to release heavy metal atoms. The heavy metal atoms are excited by the interaction with other atoms in the plasma, thereby generating extreme ultraviolet light.

[0054] By applying the solution of the embodiment of the present application, since the heavy metal injection device can continuously inject the target mass of the specified heavy metal into the magnetic confinement device, the problem of high production cost of the extreme ultraviolet light source due to waste of the specified heavy metal is avoided, and the situation of instability of the extreme ultraviolet light due to insufficient specified heavy metal is also avoided. In addition, the continuous injection of the specified heavy metal further ensures the stability of the extreme ultraviolet light source.

[0055] In one embodiment, before controlling the heavy metal injection device to continuously inject the target mass of the designated heavy metal into the magnetic confinement device, the target mass of the designated heavy metal can also be determined. There are many ways to determine the target mass, which can be selected according to actual conditions, and the present application embodiment does not impose any limitation on this.

[0056] In a possible implementation of the present application, the target mass may be randomly generated.

[0057] In another possible implementation of the present application, in general, the designated heavy metal cannot be completely ionized in the magnetic confinement device. Therefore, the target mass can be determined according to the ionization rate of the designated heavy metal injected into the magnetic confinement device. That is, before the above-mentioned control of the heavy metal injection device to continuously inject the designated heavy metal of the target mass into the magnetic confinement device, the following steps may also be included:

[0058] The target mass of the specified heavy metal is determined based on the optical power of the EUV light and the ionization rate of the specified heavy metal.

[0059] Specifically, optical power refers to the work done by extreme ultraviolet light per unit time. Since the ionization rates of different designated heavy metals are usually different, the target masses of different designated heavy metals injected into the magnetic confinement device by the heavy metal injection device are usually also different.

[0060] By applying the solution of the embodiment of the present application, the target mass is determined based on the optical power of the extreme ultraviolet light and the ionization rate of the specified heavy metal, thereby ensuring the accuracy of the target mass.

[0061] Step 106: Control the optical device to collect extreme ultraviolet light.

[0062] In one or more embodiments of the present application, a magnetic confinement device is used to generate plasma; when the plasma meets preset injection conditions, a heavy metal injection device is controlled to inject specified heavy metals into the magnetic confinement device so that the specified heavy metals react with the plasma in the magnetic confinement device to generate extreme ultraviolet light. Further, an optical device can be controlled to collect the extreme ultraviolet light.

[0063] Specifically, extreme ultraviolet light may be referred to as extreme ultraviolet radiation. The optical device includes, but is not limited to, a reflector, a filter, a focusing mirror, and a spectrometer.

[0064] By applying the solution of the embodiments of the present application, the stability of the extreme ultraviolet light is improved and the cost of generating the extreme ultraviolet light can be reduced because the magnetic confinement device that meets the requirements for generating extreme ultraviolet light has low cost, simple and stable operation, and high electro-optical conversion efficiency.

[0065] In one embodiment, after controlling the optical device to collect the extreme ultraviolet light, the optical device can be controlled to filter and focus the extreme ultraviolet light, while accurately measuring and controlling the extreme ultraviolet light, thereby ensuring the stability of the extreme ultraviolet light and the purity of the extreme ultraviolet light spectrum.

[0066] In one embodiment, before the above-mentioned controlling the heavy metal injection device to inject the designated heavy metal into the magnetic confinement device, the following steps may also be included:

[0067] Monitor plasma and obtain plasma parameters;

[0068] Determine whether the plasma meets the preset injection conditions according to the plasma parameters.

[0069] Specifically, plasma parameters include but are not limited to density, temperature, shape, impurities, and magnetic field.

[0070] It should be noted that when determining whether the plasma meets the preset injection conditions based on the plasma parameters, the reference parameters corresponding to the plasma meeting the preset injection conditions can be obtained, and the monitored plasma parameters and the reference parameters can be compared. If the plasma parameters do not reach the reference parameters, it means that the plasma does not meet the preset injection conditions; if the plasma parameters reach the reference parameters, it means that the plasma meets the preset injection conditions, wherein the reference parameters are generally density 10 18 m -3 , electron temperature 10 million degrees, plasma current 100kA.

[0071] By applying the solution of the embodiment of the present application, the plasma is monitored and the plasma parameters are obtained; based on the plasma parameters, it is determined whether the plasma meets the preset injection conditions. Only when the plasma meets the preset injection conditions will the heavy metal injection device be controlled to inject the specified heavy metal into the magnetic confinement device, thereby ensuring that when the specified heavy metal is injected into the magnetic confinement device, the plasma meets the preset injection conditions, further ensuring the stability of the extreme ultraviolet light generation.

[0072] In one embodiment, after determining whether the plasma meets the preset injection conditions according to the plasma parameters, the following steps may also be included:

[0073] When the plasma does not meet the preset injection conditions, the plasma parameters are adjusted.

[0074] It should be noted that, if the plasma does not meet the preset injection conditions, the heavy metal injection device will not inject the specified heavy metal into the magnetic confinement device. In order to generate extreme ultraviolet light, in the embodiment of the present application, the plasma parameters can be adjusted until the plasma meets the preset injection conditions, and then the heavy metal injection device will be controlled to inject the specified heavy metal into the magnetic confinement device.

[0075] By applying the solution of the embodiment of the present application, when the plasma does not meet the preset injection conditions, the plasma parameters are adjusted to achieve precise control of the plasma parameters such as density, temperature, and shape, thereby making the extreme ultraviolet light more stable.

[0076] In one embodiment, after the above-mentioned control optical device collects extreme ultraviolet light, the following steps may also be included:

[0077] Collect and record plasma parameters and EUV light parameters.

[0078] It should be noted that after collecting and recording the plasma parameters and the extreme ultraviolet light parameters, it is possible to determine whether the extreme ultraviolet light generated by the extreme ultraviolet light source assembly meets actual needs based on the plasma parameters and the extreme ultraviolet light parameters. If it does not meet actual needs, it is returned to regenerate the extreme ultraviolet light.

[0079] By applying the solution of the embodiment of the present application, plasma parameters and extreme ultraviolet light parameters are collected and recorded, ensuring that the operation process of the extreme ultraviolet light source assembly is traceable.

[0080] See also Figure 2 , Figure 2 FIG. 1 shows an architecture diagram of an extreme ultraviolet light source assembly provided by an embodiment of the present application, such as Figure 2 As shown, the extreme ultraviolet light source assembly includes a magnetic confinement device 100, a heavy metal injection device 200 and an optical device 300, and the heavy metal injection device 200 is connected to the magnetic confinement device 100;

[0081] A magnetic confinement device 100 for generating plasma;

[0082] The heavy metal injection device 200 is used to inject a specified heavy metal into the magnetic confinement device 100 when the plasma meets the preset injection conditions, so that the specified heavy metal reacts with the plasma in the magnetic confinement device 100 to generate extreme ultraviolet light;

[0083] The optical device 300 is used to collect extreme ultraviolet light.

[0084] By applying the solution of the embodiments of the present application, the stability of the extreme ultraviolet light is improved and the cost of generating the extreme ultraviolet light can be reduced because the magnetic confinement device that meets the requirements for generating extreme ultraviolet light has low cost, simple and stable operation, and high electro-optical conversion efficiency.

[0085] In one embodiment, the magnetic confinement device 100 includes a tokamak, which includes a vacuum chamber, a magnet, and a radio frequency wave antenna;

[0086] a vacuum chamber to contain the plasma;

[0087] A magnet, used for generating a magnetic field to confine the plasma in the vacuum chamber through the magnetic field;

[0088] The radio frequency wave antenna is used to send microwaves or millimeter waves into the vacuum chamber so that the microwaves or millimeter waves are coupled with the plasma and drive the plasma current.

[0089] It should be noted that the vacuum chamber is the core part of the Tokamak. The vacuum chamber is generally made of stainless steel and has high vacuum and high temperature resistance to ensure the stable operation of the Tokamak. The maximum radius of the vacuum chamber is generally 1.2m to 1.3m, and the minimum radius is generally 0.2m to 0.3m.

[0090] Magnets are used to generate strong magnetic fields to control the movement of plasma produced by the Tokamak through magnetic fields, and can also control the shape of plasma produced by the Tokamak through magnetic fields. Magnets are made of superconducting coils, which can achieve zero resistance at low temperatures, thereby improving the stability and efficiency of the magnetic field. The toroidal magnetic field strength is generally 1T to 2T.

[0091] RF wave antennas generally use phased waveguide arrays, which adjust the phase difference between the main waveguides to reduce the antenna reflection coefficient, thereby improving the plasma current driving efficiency. Microwaves or millimeter waves can heat plasma and drive plasma current. The working principle of microwaves or millimeter waves and plasma includes low hybrid resonance or electron cyclotron resonance.

[0092] In the embodiment of the present application, the vacuum chamber contains plasma; the magnet generates a magnetic field to control the movement of plasma in the vacuum chamber through the magnetic field; the radio frequency wave antenna sends microwaves or millimeter waves into the vacuum chamber to couple the microwaves or millimeter waves with the plasma and drive the plasma current. Since the plasma generated by the tokamak can be well confined in the vacuum chamber by the magnetic field, the corrosion and burning of the wall material of the emitting light source by the plasma is effectively reduced, and the life of the extreme ultraviolet light source assembly and the light source is extended.

[0093] In one embodiment, the extreme ultraviolet light source assembly further includes a monitoring device;

[0094] The monitoring device is used to monitor the plasma and obtain the plasma parameters; determine whether the plasma meets the preset injection conditions according to the plasma parameters; when the plasma meets the preset injection conditions, send an injection instruction to the heavy metal injection device 200 so that the heavy metal injection device 200 injects the specified heavy metal into the magnetic confinement device 100.

[0095] It should be noted that during the process of extreme ultraviolet light generation, the monitoring device can be controlled to monitor the plasma parameters such as density, temperature, impurities and magnetic field in real time. The monitoring device can be called a plasma density, temperature, impurity, and magnetic field diagnostic device. The monitoring device includes but is not limited to a microwave interferometer, a Langmuir probe, a magnetic probe, and a variety of radiation diagnostics (hard X-rays, soft X-rays, AXUV detectors).

[0096] In one embodiment, the extreme ultraviolet light source assembly further includes a control device;

[0097] The control device is used to adjust the plasma parameters when the plasma does not meet the preset injection conditions.

[0098] It should be noted that during the EUV light generation process, the control device can adjust the plasma parameters, realizing real-time regulation and control of the EUV light source assembly to maintain a stable plasma state and optimize the light source output.

[0099] In one embodiment, the extreme ultraviolet light source assembly further includes a data acquisition device;

[0100] The data acquisition device is used to collect and record plasma parameters and extreme ultraviolet light parameters.

[0101] It should be noted that during the generation of extreme ultraviolet light, the data acquisition device can be controlled to monitor and record the discharge process of the extreme ultraviolet light source assembly, such as recording plasma parameters and extreme ultraviolet light parameters. After the discharge is completed, the components in the extreme ultraviolet light source assembly can be further controlled to be gradually shut down, and necessary maintenance and repairs can be performed on the extreme ultraviolet light source assembly to ensure the long-term stable operation of the extreme ultraviolet light source assembly.

[0102] See also Figure 3 , Figure 3 1 shows an architecture diagram of an optical system provided by an embodiment of the present application, wherein the optical system includes an extreme ultraviolet light source assembly; Figure 3 As shown, the magnetic confinement device included in the extreme ultraviolet light source assembly is a tokamak, and the extreme ultraviolet light source assembly also includes a heavy metal injection device 200, an optical device 300, a monitoring device 400, a control device 500, and a data acquisition device 600, wherein the tokamak includes a vacuum chamber 1002, a magnet 1004, a magnet power supply 1006, a radio frequency power source 1008, a radio frequency wave antenna 1010, an air pump group 1012, and an air intake valve assembly 1014;

[0103] A vacuum chamber 1002 for containing plasma;

[0104] A magnet 1004, used to generate a magnetic field to confine the plasma in the vacuum chamber 1002 through the magnetic field;

[0105] A magnet power supply 1006 for providing current to the magnet 1004;

[0106] A radio frequency power source 1008, used to generate high-power microwaves or millimeter waves;

[0107] A radio frequency wave antenna 1010 is used to send microwaves or millimeter waves into the vacuum chamber 1002 so that the microwaves or millimeter waves are coupled with the plasma and drive the plasma current;

[0108] The vacuum pump group 1012 is used to exhaust the gas in the vacuum chamber 1002 to maintain a high vacuum environment;

[0109] An inlet valve assembly 1014 for controlling the rate and type of gas entering the vacuum chamber 1002;

[0110] The monitoring device 400 is used to monitor the plasma and obtain the plasma parameters; determine whether the plasma meets the preset injection conditions according to the plasma parameters; and send an injection instruction to the heavy metal injection device 200 when the plasma meets the preset injection conditions, so that the heavy metal injection device 200 injects the specified heavy metal into the tokamak;

[0111] A control device 500, used to adjust plasma parameters when the plasma does not meet the preset injection conditions;

[0112] A data acquisition device 600, for collecting and recording plasma parameters and extreme ultraviolet light parameters;

[0113] The heavy metal injection device 200 is used to inject a specified heavy metal into the tokamak when the plasma meets the preset injection conditions, so that the specified heavy metal reacts with the plasma in the tokamak to generate extreme ultraviolet light;

[0114] The optical device 300 is used to collect, filter and focus extreme ultraviolet light, and is also used to measure and control the extreme ultraviolet light.

[0115] It should be noted that the RF power source 1008 can use a magnetron, the microwave frequency is generally 2.45 GHz, and the power is hundreds of kilowatts to megawatts. The vacuum pump group 1012 generally includes a molecular pump, a mechanical pump, and an ion pump to provide a sufficient vacuum rate. By adjusting the inlet valve assembly 1014, the composition and density of the plasma can be adjusted. The working gas is generally hydrogen.

[0116] By applying the solution of the embodiment of the present application, since the tokamak used to generate extreme ultraviolet light is low-cost, reusable and can achieve stable operation, the extreme ultraviolet light source assembly can generate stable plasma and stable extreme ultraviolet light, and can also reduce the manufacturing cost of the light source. In addition, the plasma generated by the extreme ultraviolet light source assembly can be well confined in the vacuum chamber by the magnetic field, thereby effectively reducing the corrosion and burning of the light source wall material by the plasma, and extending the life of the extreme ultraviolet light source assembly and the light source. The control device adjusts the parameters based on the plasma parameters fed back in real time by the monitoring device, and realizes precise control of the density, temperature, shape and other parameters of the plasma, thereby making the extreme ultraviolet light more stable.

[0117] In one embodiment of the present application, the optical system may further include a component control unit, which may be any type of stationary or mobile computing device, including a mobile computer or mobile computing device (e.g., a tablet computer, a personal digital assistant, a laptop computer, a notebook computer, a netbook, etc.), a mobile phone (e.g., a smart phone), a wearable computing device (e.g., a smart watch, smart glasses, etc.), or other types of mobile devices, or a stationary computing device such as a desktop computer or a personal computer (PC). The component control unit may also be a mobile or stationary server.

[0118] The component control unit is used to execute computer executable instructions, and when the computer executable instructions are executed by the component control unit, the steps of the above-mentioned extreme ultraviolet light generation method are implemented.

[0119] The above is a schematic scheme of a component control unit of this embodiment. It should be noted that the technical scheme of the component control unit and the technical scheme of the above-mentioned extreme ultraviolet light generation method belong to the same concept, and the details not described in detail in the technical scheme of the component control unit can be referred to the description of the technical scheme of the above-mentioned extreme ultraviolet light generation method.

[0120] An embodiment of the present application further provides a computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, can implement the steps of the above-mentioned extreme ultraviolet light generation method.

[0121] The above is a schematic scheme of a computer-readable storage medium of this embodiment. It should be noted that the technical scheme of the storage medium and the technical scheme of the above-mentioned extreme ultraviolet light generation method belong to the same concept, and the details not described in detail in the technical scheme of the storage medium can be referred to the description of the technical scheme of the above-mentioned extreme ultraviolet light generation method.

[0122] An embodiment of the present application further provides a computer program, wherein when the computer program is executed in a computer, the computer is caused to execute the steps of the above-mentioned extreme ultraviolet light generating method.

[0123] The above is a schematic scheme of a computer program of this embodiment. It should be noted that the technical scheme of the computer program and the technical scheme of the above-mentioned extreme ultraviolet light generation method belong to the same concept, and the details not described in detail in the technical scheme of the computer program can be referred to the description of the technical scheme of the above-mentioned extreme ultraviolet light generation method.

[0124] The above describes specific embodiments of the present application. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recorded in the claims can be performed in an order different from that in the embodiments and still achieve the desired results. In addition, the processes depicted in the accompanying drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0125] The computer executable instructions include computer program codes, which may be in source code form, object code form, executable files or some intermediate forms, etc. The computer readable medium may include: any entity or device capable of carrying the computer program code, recording medium, USB flash drive, mobile hard disk, magnetic disk, optical disk, computer memory, read-only memory (ROM), random access memory (RAM), electric carrier signal, telecommunication signal and software distribution medium, etc. It should be noted that the content contained in the computer readable medium may be appropriately increased or decreased according to the requirements of patent practice. For example, in some regions, according to patent practice, computer readable media do not include electric carrier signals and telecommunication signals.

[0126] It should be noted that, for the aforementioned method embodiments, for the sake of simplicity of description, they are all expressed as a series of action combinations, but those skilled in the art should be aware that the embodiments of the present application are not limited by the described action sequence, because according to the embodiments of the present application, certain steps can be performed in other sequences or simultaneously. Secondly, those skilled in the art should also be aware that the embodiments described in this application are all preferred embodiments, and the actions and modules involved are not necessarily required by the embodiments of the present application.

[0127] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0128] The preferred embodiments of the present application disclosed above are only used to help explain the present application. The embodiments do not describe all the details in detail, nor do they limit the invention to the specific implementation methods described. Obviously, many modifications and changes can be made according to the content of the embodiments of the present application. The present application selects and specifically describes these embodiments in order to better explain the principles and practical applications of the embodiments of the present application, so that those skilled in the art can understand and use the present application well. The present application is only limited by the claims and their full scope and equivalents.

Claims

1. A method for generating extreme ultraviolet light, characterized in that: include: Generate plasma using magnetic confinement device; When the plasma meets the preset injection conditions, controlling the heavy metal injection device to inject the specified heavy metal into the magnetic confinement device, so that the specified heavy metal reacts with the plasma in the magnetic confinement device to generate extreme ultraviolet light; An optical device is controlled to collect the extreme ultraviolet light.

2. The method according to claim 1, characterized in that The designated heavy metal includes at least one of tin powder, tungsten powder, nickel powder and tantalum powder.

3. The method according to claim 1, characterized in that The magnetic confinement device comprises any one of a tokamak, a stellarator, a magnetic mirror, a field inversion configuration, and an inverted field pinch.

4. The method according to claim 1, characterized in that The controlling heavy metal injection device to inject a specified heavy metal into the magnetic confinement device comprises: The heavy metal injection device is controlled to continuously inject a target mass of a designated heavy metal into the magnetic confinement device.

5. The method according to claim 4, characterized in that Before the heavy metal injection device is controlled to continuously inject the target mass of the designated heavy metal into the magnetic confinement device, the method further comprises: The target mass of the specified heavy metal is determined based on the optical power of the EUV light and the ionization rate of the specified heavy metal.

6. The method according to claim 1, characterized in that Before the controlling heavy metal injection device to inject the designated heavy metal into the magnetic confinement device, the method further comprises: monitoring the plasma to obtain plasma parameters; Determine whether the plasma meets a preset injection condition according to the plasma parameters.

7. The method according to claim 6, characterized in that After determining whether the plasma meets the preset injection condition according to the plasma parameters, the method further includes: When the plasma does not satisfy the preset injection condition, the plasma parameter is adjusted.

8. The method according to claim 1, characterized in that: After the control optical device collects the extreme ultraviolet light, the control optical device further comprises: Collect and record plasma parameters and EUV light parameters.

9. The method according to claim 1, characterized in that: After the control optical device collects the extreme ultraviolet light, the control optical device further comprises: The optical device is controlled to filter and focus the extreme ultraviolet light.

10. An extreme ultraviolet light source assembly, characterized in that: It comprises a magnetic confinement device, a heavy metal injection device and an optical device, wherein the heavy metal injection device is connected to the magnetic confinement device; The magnetic confinement device is used to generate plasma; The heavy metal injection device is used to inject a specified heavy metal into the magnetic confinement device when the plasma meets a preset injection condition, so that the specified heavy metal reacts with the plasma in the magnetic confinement device to generate extreme ultraviolet light; The optical device is used to collect the extreme ultraviolet light.

11. The extreme ultraviolet light source assembly according to claim 10, characterized in that: The magnetic confinement device comprises a tokamak, wherein the tokamak comprises a vacuum chamber, a magnet and a radio frequency wave antenna; The vacuum chamber is used to contain plasma; The magnet is used to generate a magnetic field to confine the plasma in the vacuum chamber through the magnetic field; The radio frequency wave antenna is used to send microwaves or millimeter waves into the vacuum chamber so that the microwaves or millimeter waves are coupled with the plasma and drive the plasma current.

12. The extreme ultraviolet light source assembly according to claim 10, characterized in that: The extreme ultraviolet light source assembly also includes a monitoring device; The monitoring device is used to monitor the plasma and obtain plasma parameters; and determine whether the plasma meets the preset injection conditions according to the plasma parameters; When the plasma meets the preset injection condition, an injection instruction is sent to the heavy metal injection device, so that the heavy metal injection device injects the designated heavy metal into the magnetic confinement device.

13. The extreme ultraviolet light source assembly according to claim 10, characterized in that: The extreme ultraviolet light source assembly also includes a control device; The control device is used to adjust the plasma parameters when the plasma does not meet the preset injection conditions.

14. The extreme ultraviolet light source assembly according to claim 10, characterized in that: The extreme ultraviolet light source assembly also includes a data acquisition device; The data acquisition device is used to collect and record plasma parameters and extreme ultraviolet light parameters.

15. An optical system, characterized in that: include: An extreme ultraviolet light source assembly as claimed in any one of claims 10 to 14.

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